diff --git a/third_party/tvl/third_party/bat_syntaxes/default.nix b/third_party/tvl/third_party/bat_syntaxes/default.nix
index 15af130916..457c3fb124 100644
--- a/third_party/tvl/third_party/bat_syntaxes/default.nix
+++ b/third_party/tvl/third_party/bat_syntaxes/default.nix
@@ -9,10 +9,12 @@
 let
   inherit (pkgs) bat runCommand;
 in
-runCommand "bat-syntaxes.bin" { } ''
+runCommand "bat-syntaxes.bin" {
+  nativeBuildInputs = [ bat ];
+} ''
   export HOME=$PWD
   mkdir -p .config/bat/syntaxes
   cp ${./Prolog.sublime-syntax} .config/bat/syntaxes
-  ${bat}/bin/bat cache --build
+  bat cache --build
   mv .cache/bat/syntaxes.bin $out
 ''
diff --git a/third_party/tvl/third_party/nixpkgs/default.nix b/third_party/tvl/third_party/nixpkgs/default.nix
index 50bdcb8afe..6f91d31e7a 100644
--- a/third_party/tvl/third_party/nixpkgs/default.nix
+++ b/third_party/tvl/third_party/nixpkgs/default.nix
@@ -11,6 +11,8 @@
 { depot ? { }, externalArgs ? { }, depotOverlays ? true, ... }:
 
 let
+  system = if externalArgs ? nixpkgsSystem then externalArgs.nixpkgsSystem else builtins.currentSystem;
+
   # import the nixos-unstable package set, or optionally use the
   # source (e.g. a path) specified by the `nixpkgsBisectPath`
   # argument. This is intended for use-cases where the depot is
@@ -20,7 +22,7 @@ let
 
   # Stable package set is imported, but not exposed, to overlay
   # required packages into the unstable set.
-  stableNixpkgs = import depot.third_party.sources.nixpkgs-stable { };
+  stableNixpkgs = import depot.third_party.sources.nixpkgs-stable { inherit system; };
 
   # Overlay for packages that should come from the stable channel
   # instead (e.g. because something is broken in unstable).
@@ -47,7 +49,7 @@ import nixpkgsSrc {
       allowUnfree = true;
       allowBroken = true;
     };
-  system = if externalArgs ? nixpkgsSystem then externalArgs.nixpkgsSystem else builtins.currentSystem;
+  inherit system;
 
   overlays = [
     commitsOverlay